Healthy Gut, Healthy Brain
MEET YOUR SECOND BRAIN
Understanding just how closely the gut and the brain are related is essential.
Think of the last time you felt sick to your stomach because you were anxious, scared, or over-the-moon elated. Scientists are learning that this intimate relationship between the gut and the brain is bidirectional: Just as your brain can send butterflies to your stomach, your gut can relay its state of calm or alarm to the brain.
The vagus nerve, the longest of 12 cranial nerves, is the primary channel between millions of nerve cells in our intestinal nervous system (sometimes called the enteric nervous system) and our central nervous system, which comprises the brain and spinal cord. “Vagus” is Latin for “wanderer,” an apt name for this nerve that runs outside the brain and through the digestive system. The vagus extends from the brain stem to the abdomen, directing many bodily processes that don’t require thought, like heart rate and digestion.
At the same time, the bacteria in the gut directly affect the function of the cells along the vagus nerve. And some of the gut’s nerve cells and microbes release neurotransmitters that speak to the brain in its own language.
The neurons in the gut are so innumerable that many scientists are now calling them the “second brain.” This second brain not only regulates muscle function, immune cells, and hormones, but also manufactures an estimated 80 to 90 percent of serotonin (the “feel-good” neurotransmitter).
This means the gut’s brain makes more serotonin — the master happiness molecule — than the brain in your head. Many neurologists and psychiatrists are now realizing that this may be one reason antidepressants are often less effective in treating depression than proper dietary changes.
Perhaps the most significant factor related to the health of the microbiome — and thus, the brain — is the food we eat. It is also the greatest challenge to the microbiome and brain. Food matters enormously, trumping other factors in our lives that we may not be entirely able to control.
5 WAYS TO BOOST YOUR BRAIN THROUGH YOUR GUT
I am frequently asked how long it takes to rehabilitate a dysfunctional or underperforming microbiome. Research shows that significant changes in the array of gut bacteria can take place in as little as six days after instituting a new dietary protocol, like the one I present in my book (the highlights of which I’m sharing here). But everyone is different; your Brain Maker rehab will depend on the current state of your gut and how quickly you commit to making changes.
1. EAT FOODS RICH IN PROBIOTICS
Probiotics are live bacteria and yeast that support good digestive health. Long before probiotics became available in supplement form, the health benefits of fermented, probiotic-rich foods like kimchi, sauerkraut, and yogurt were well recognized. The Chinese were fermenting -cabbage 6,000 years ago.
2. GO LOWER-CARB; EMBRACE HIGH-QUALITY FATS
A diet that keeps your blood sugar balanced keeps your gut bacteria balanced. A diet high in rich sources of fiber from whole vegetables and fruits feeds good gut bacteria and produces the right balance of short-chain fatty acids to keep the intestinal lining in check. A diet that’s intrinsically anti-inflammatory is good for the brain.
Diets high in sugar and low in fiber fuel unwanted bacteria and increase the chances of intestinal permeability, mitochondrial damage, a compromised immune system, and widespread inflammation that can reach the brain. It’s a vicious cycle; all of these further disrupt our protective microbial balance.
3. ENJOY CHOCOLATE, COFFEE, WINE, AND TEA
You can rejoice in the fact that, as far as your brain’s health is concerned, you can embrace chocolate, coffee, and wine in moderation, and tea to your heart’s desire.
Research abounds concerning dark chocolate’s benefits. In one study, Italian researchers demonstrated that in elderly individuals suffering mild cognitive impairment, those who consumed the highest level of flavonols (one category of polyphenols) from cocoa and chocolate showed heightened cognitive function. On that note, Spanish researchers have found that LPS levels, a marker for both inflammation and intestinal permeability, were dramatically reduced in individuals who consumed red wine in moderation (one to two glasses per day).
4. CONSUME FOODS RICH IN PREBIOTICS
Prebiotics are food-borne fuel for the beneficial bacteria that live in the gut, and they occur naturally in raw garlic, cooked and raw onions, leeks, chicory, Jerusalem artichokes, and jicama. Estimates suggest that for every 100 grams of prebiotic carbohydrates we consume, a full 30 grams of good gut bacteria are produced. Prebiotics have many additional benefits, including the ability to reduce inflammation in inflammatory-bowel disorders, enhance mineral absorption, and promote a sense of satiety. Animals given prebiotics produce less ghrelin, the hormone that signals the brain that it’s time to eat.
5. DRINK FILTERED WATER
Consuming plenty of water is important to intestinal health, but it’s critical that the water doesn’t contain gut-busting chemicals like chlorine. Environmental toxins can disrupt the microbiome and disturb brain physiology. I recommend using a household water filter. There are a variety of home water-treatment technologies available, from simple filtration pitchers to under-sink units with a separate spigot. Make sure the filter you buy removes chlorine as well as other contaminants, and be sure to maintain and change it regularly.
Finally, ditch plastic water bottles and choose reusable bottles made from stainless steel or glass instead.